The thing is, the watch does have a use case, it's just one that’s hard for Apple to talk about. Last week Matthew Panzarino at TechCrunch wrote that the best thing about the watch, according to the Apple employees who’ve been demoing it, was that it let them basically stop using their phone. Instead of fishing their phones out of their pockets every couple minutes, they could check incoming notifications on the watch and choose to ignore or respond to them.
This, one hundred times this. The real benefit of the Apple Watch is that it takes things that are a pain on the phone and makes them easier. To really show off how good the Watch can be, they'd have to point out flaws with the iPhone. That's not something Apple, who is basically "the iPhone company" right now, has to do very carefully.